Centrifugal amalgamator



April 8, 1924. 1,489,670

G. c. RICHARDS CENTRIFUGAL AMALGAMATQR Filed Dec. 21. 1822 INVENTOR. R S50E65 cave/mew 5 W, M I

ATTOR YS.

Patented Apr. 8, 19.24.

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GEORGE C. RICHARDS, F BERKELEY, CALIFORNIA, ASSIGNOE OF ONE-HALF TO HARRY 1 NISSEN'.

CENTRIFUGAL AMALGAMATOR.

Application filed December 21, 1922.

To all whom it may concern:

Be it known that I, GEORGE C. RICHARDS,

a citizen of the United States, residing at Berkeley, county of Alameda, and State of 5 California, have invented new and useful Improvements in Centrifugal Amalgamators, of which the following is a specification.

This invention relates to apparatus for re covering precious metal from pulverized ore and precious metal bearing sand, and particularly pertains to a centrifugal amalgamator.

It is the principal object of the present invention to provide a generally improved and simplified amalgamator employing a centrifugal bowl containing mercury for re moving the precious contents of pulverized ore or precious metal bearing sand which is forced through the mercury by hydrostatic head given the ore or sand when entering the apparatus.

By my invention I maintain a body of fluid mercury through which the pulverized ore or precious metal bearing sand is kept constantly moving by the hydrostatic head given the pulp or sand entering the machine. By this means the precious metal contents of the pulp or sand are brought into intimate contact with the mercury with which they amalgamate.

One form which the invention may assume is exemplified in the following description and illustrated by way of example in the accompanying drawings, in which:

Fig. 1 is a vertical section through the preferred embodiment of the machine.

Fig. 2 is a perspective view of the stationary vaned collar.

Referring more particularly to the accompanying drawings, I show a main frame 10 fitted with bearings 11 for the reception of a vertical shaft 12. A centrifugal bowl 14 is fixed at the upper end of this shaft and comprises a cylindrical lower portion 15 con stituting a mercury chamber and a frustoconical upper portion 16. A stationary cylindrical feed spout 17 is mounted above the bowl 14. The upper end of this spout is fitted with a feed hopper 18 for receiving material from a feed launder 19. The lower end of the feed spout is open and projects downwardly into the mercury chamber to a point short of the bottom thereof.

To prevent clogging of the feed spout and Serial N'o. 608,170.

to agitate the mercury at the point where the material contacts therewith, I provide a vertical screw agitator 20. This agitator is fixed at its lower end in the bottom of the bowl 14 and extends upwardly within the feed spout 17 as shown.

The lower end of the feed spout is fitted with a collar 21 having radial vanes 22 projecting therefrom. These vanes retard the movement of the mercury and serve to prevent the mercury from being thrown from bowl when the latter is revolving rap- 1 y. l

To impart rotation to the bowl, I fit the vertical shaft 12 with a bevel gear 23 which is in constant mesh with a bevel gear 24 fixed on a drive shaft 25. This shaft is "journaled in bearings 26 fixed on the frame and is fitted with a driving pulley 27 mounted on its outer end. This pulley may be connected by a belt to any suitable driving mechanism.

In operationof'the apparatus, sufiicient mercury is introduced into the mercury chamber to close the end of the feed spout, and material is fed into the feed spout from the launder 19. As the lower end of the feed spout extends downwardly into the mercury and has its exit closed thereby, the effect is to force the pulp through the mercury by means of hydrostatic head built up in the feed spout 17. This brings the material and particles of precious metal into intimate contact with the mercury. The material, having passed through the mercury and deposited its particles of precious metal therein, is discharged over the top of the bowl and enters a discharge launder 28. The mercury may be drawn off when desired by removing the screw plug 30.

Due to the provision of the vanes 22 and overhanging ledges 29, the centrifugal action of the bowl will not cause the mercury to rise therein. The loss of mercury will therefore be minimized. Also, due to the provision of the agitator 20, clogging of the feed spout will be prevented and the material will be agitated at the point where it enters the mercury. This insures that the particles composing the material or pulp will be subjected to intimate contact with the mercury, insuring thorough separation.

While I have shown and described my invention in the form now preferred by me, it is understood that various changes in the combination, construction and arrangement of the various parts may be made by those skilled in the art, without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. An amalgamator comprising a main frame, a bowl rotatably mounted thereon, the upper portion of the bowl being frustoconical, the lower portion of the bowl being cylindrical and constituting a chamber for containing fluid mercury, a stationary vertical feed spout arranged above the bowl with its lower end extending into the mercury in said chamber, radial vanes fixed on the lower end of said feed spout whereby to prevent centrifugal action of the bowl from discharging the mercury, and an annular overhanging lip at the junction of the frustoconical and cylindrical portions of the bowl to assist the radial vanes in preventing the discharge of mercury from the bowl.

2. An amalgamator comprising a main frame, a bowl rotatably mounted thereon, the upper portion of the bowl being frustoconical, the lower portion of the bowl being cylindrical and constituting a chamber for containing fluid mercury, a stationary cylin drical feed spout mounted above the bowl with its lower end extending into the mercury in said chamber, a rotatable agitator carried by the bowl and extending upwardly into the feed spout, said agitator being adapted to assist in feeding material downwardly through the spout and agitate it at the point where it contacts with the mercury, and an annular overhanging lip at the junction of the frusto-conical and cylindrical portions of the bowl to prevent the accidental discharge of the mercury in the bowl.

An amalgamator comprising a main frame, a bowl rotatably mounted thereon, the upper portion of the bowl being frustoconical, the lower portion of the bowl being cylindrical and constituting a mercury chamber, a cylindrical feed spout mounted above the bowl and extending downwardly into the mercury in said chamber, radial vanes fixed on the lower end of the feed spout whereby to prevent the centrifugal action of the bowl from discharging the mercury.

4;. An a-malgainator comprising a main frame, a rotatable bowl mounted thereon, said bowl adapted to contain fluid mercury, a vertically disposed feed spout mounted above the bowl with its lower end projecting into the mercury in the bowl, agitating means in said spout and operable to assist in feeding material downwardly therethrough and to agitate it at the point where it contacts with the mercury in the bowl, and radial vanes fixed on the lower end of said spout whereby to prevent centrifugal action of the bowl from discharging the mercury.

GEORGE C. RICHARDS. 

